Thanks Bomber, most helpful. It must be my age or something, youtube is normally the last place I think to look for advice!
I had already worked out how to free up the 3rd lambda cable by then, but I had to cut 3 cable ties to be sure there was enough slack; 2 of them could only be reached by sawing away deep inside the bike with a long, thin kitchen knife.
I had done a few hundred miles with some SS Arrow headers which sounded brilliant, especially with the quickshifter blips, but were just a bit too noisy at fast idle on a cold start for an early shift. I must get round to putting the things up for sale when I can be arsed…
The Akra items, with their “pre-muffler” are a little bit quieter at start-up, but still sound good on the move, this is using the stock silencer which is pleasingly light and unrestrictive.